It is known to prepare one or more middle distillate fractions such as for example kerosene or gasoil and a base oil precursor or a base oil from a Fischer-Tropsch derived feedstock.
In WO02/076027 for example, is disclosed a process wherein two or more lubricating base oil grades and a gas oil are obtained by hydrocracking/hydroisomerising a C5+ Fisher-Tropsch product over a catalyst comprising platinum supported on a silica-alumina carrier prepared from amorphous silica-alumina and separating the product thus obtained in one or more gasoil fractions and a base oil precursor fraction. After performing a pour point reducing step, for example catalytic dewaxing, to the base oil precursor fraction, the base oil precursor fraction is separated into two or more base oil grades.
In WO2009/080681 is disclosed a process to prepare a gas oil and a base oil from a Fischer-Tropsch derived feedstock, wherein the feedstock is subjected to a hydroprocessing step to obtain an isomerised feedstock, separating the isomerised feedstock by means of distillation into at least a gas oil fraction, a heavy distillate fraction and a residual fraction, recycling at least part of the heavy distillate fraction to the hydroprocessing step and reducing the pour point of the residual fraction by means of catalytic dewaxing to obtain the base oil.
There is, however, still a need for improvement of middle distillate products and base oils from paraffinic feedstocks, such as Fischer-Tropsch derived feedstocks, in particular with respect to the cold flow properties of the base oil and/or middle distillate products.